Flatulence produced when air escapes your anus at the same time as a solid object. Although usually associated with that high pitched fart that comes out as you take a huge dump, it is also much like what results from air being forced up your anus while participating in anal sex.

The headboard thumping and the quiet tweetering on the other side of the wall could only mean one thing: anal sex.

The soft tweeters in the bathroom were a sure sign that the one working stall was occupied.